Insulating materials are non-conductive materials under allowable voltage, but not absolutely non-conductive materials. Under a certain external electric field strength, they can also undergo processes such as conductivity, polarization, loss, breakdown, and aging after long-term use. Its resistivity is very high, usually in the range of 1010 to 1022 Ω· m. In a motor, the insulation material around the conductor separates the turns and the grounded stator core to ensure the safe operation of the motor. Insulating materials, also known as dielectrics, refer to substances that do not conduct electricity or have very little conductivity under the action of direct current voltage, and their resistivity is generally greater than 1010 Ω · m. The main function of insulation materials is to isolate charged conductors with different potentials in electrical equipment, allowing current to flow along a certain path. They can also serve as mechanical support and fixation, as well as arc extinguishing, heat dissipation, energy storage, moisture-proof, mold proof, or to improve the potential distribution of electric fields and protect conductors. Therefore, it is required that the insulation material has the highest possible insulation resistance, heat resistance, moisture resistance, and also requires a certain degree of mechanical strength